Effects of Applying High-Speed Congestion Control Algorithms in Satellite Network

In recent years, many high-speed congestion control (HSCC) algorithms have been proposed for utilizing network pipes with huge bandwidth-delay product (BDP), and some of them have also been implemented in popular operating systems. Considering the extremely long round trip propagation delay (RTPD) of satellite network, it is very likely that these algorithms are triggered when TCP flows pass through satellite network. But the existing algorithms are normally evaluated on network pipes with high bandwidth and moderate RTPD (< 400 ms). This paper is an attempt to study these algorithms on a simulated satellite network with moderate bandwidth and extremely long RTPD. Their effects on the existing applications, especially World Wide Web (WWW) and the emerging streaming applications, are emphasized. Different queue sizes are also used in simulation with the aim of investigating how to provision satellite link's queue for well accommodating flows driven by HSCC algorithms. Through this study, we find that Compound-TCP, Cubic-TCP, and H-TCP can not work well on satellite network. Currently, satellite link should use moderate queue size for accommodating flows driven by HSCC algorithms. As for end hosts, when they find that round trip time (RTT) is very long, HS-TCP should be adopted for high throughput while avoiding to hurt the existing applications as little as possible.